CVE-2026-41429: CWE-121: Stack-based Buffer Overflow in espressif arduino-esp32
arduino-esp32 is an Arduino core for the ESP32, ESP32-S2, ESP32-S3, ESP32-C3, ESP32-C6 and ESP32-H2 microcontrollers. Prior to 3.3.8, there is a remotely reachable memory corruption issue in the NBNS packet handling path. When NetBIOS is enabled by calling NBNS.begin(...), the device listens on UDP port 137 and processes untrusted NBNS requests from the local network. The request parser trusts the attacker-controlled name_len field without enforcing a bound consistent with the fixed-size destination buffers used later in the flow. This vulnerability is fixed in 3.3.8.
AI Analysis
Technical Summary
The arduino-esp32 core for ESP32 microcontrollers (including ESP32, ESP32-S2, ESP32-S3, ESP32-C3, ESP32-C6, and ESP32-H2) contains a stack-based buffer overflow vulnerability in its NBNS packet processing prior to version 3.3.8. When NetBIOS is enabled via NBNS.begin(...), the device listens on UDP port 137 and processes NBNS requests from the local network. The vulnerability stems from the request parser trusting the attacker-controlled name_len field without enforcing bounds consistent with fixed-size destination buffers, leading to memory corruption. This issue is resolved in version 3.3.8.
Potential Impact
Successful exploitation can lead to memory corruption with high impact on confidentiality, integrity, and availability, as indicated by the CVSS score of 8.8 (AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H). An attacker on the local network can remotely trigger this vulnerability without privileges or user interaction, potentially leading to arbitrary code execution or device compromise.
Mitigation Recommendations
A patch is available and the vulnerability is fixed in arduino-esp32 version 3.3.8. Users should upgrade to version 3.3.8 or later to remediate this issue. Since this is a cloud service environment, the vendor manages remediation for the cloud-hosted service; users should verify with the vendor advisory for confirmation and ensure their devices or deployments use the patched version.
CVE-2026-41429: CWE-121: Stack-based Buffer Overflow in espressif arduino-esp32
Description
arduino-esp32 is an Arduino core for the ESP32, ESP32-S2, ESP32-S3, ESP32-C3, ESP32-C6 and ESP32-H2 microcontrollers. Prior to 3.3.8, there is a remotely reachable memory corruption issue in the NBNS packet handling path. When NetBIOS is enabled by calling NBNS.begin(...), the device listens on UDP port 137 and processes untrusted NBNS requests from the local network. The request parser trusts the attacker-controlled name_len field without enforcing a bound consistent with the fixed-size destination buffers used later in the flow. This vulnerability is fixed in 3.3.8.
CVSS v3.1
Score 8.8high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The arduino-esp32 core for ESP32 microcontrollers (including ESP32, ESP32-S2, ESP32-S3, ESP32-C3, ESP32-C6, and ESP32-H2) contains a stack-based buffer overflow vulnerability in its NBNS packet processing prior to version 3.3.8. When NetBIOS is enabled via NBNS.begin(...), the device listens on UDP port 137 and processes NBNS requests from the local network. The vulnerability stems from the request parser trusting the attacker-controlled name_len field without enforcing bounds consistent with fixed-size destination buffers, leading to memory corruption. This issue is resolved in version 3.3.8.
Potential Impact
Successful exploitation can lead to memory corruption with high impact on confidentiality, integrity, and availability, as indicated by the CVSS score of 8.8 (AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H). An attacker on the local network can remotely trigger this vulnerability without privileges or user interaction, potentially leading to arbitrary code execution or device compromise.
Mitigation Recommendations
A patch is available and the vulnerability is fixed in arduino-esp32 version 3.3.8. Users should upgrade to version 3.3.8 or later to remediate this issue. Since this is a cloud service environment, the vendor manages remediation for the cloud-hosted service; users should verify with the vendor advisory for confirmation and ensure their devices or deployments use the patched version.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-20T15:32:33.814Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
- Is Cloud Service
- true
Threat ID: 69ebeffb87115cfb687b9d71
Added to database: 4/24/2026, 10:34:35 PM
Last enriched: 5/2/2026, 7:31:22 AM
Last updated: 6/9/2026, 3:46:55 AM
Views: 159
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